JP2002291161A - Output control method for household fuel cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid frequent sudden changes in generated power output and increase use on rate of the power generating capacity even fallowing the used power considering the used conditions of household appliances. SOLUTION: Based on consumption patterns of domestic power in a unit period such as one day, an overall time zone is divided into a plurality of time zones such as a time zone in which home appliances of large power consumption operate for a short time, and a time zone in which the home appliances consumes less power because they are not operated less and the power is continuously consumed with less fluctuations. Deviations from the power consumptions corresponding to the respective time zones, the increasing rate of the quantity of generated power, and the increasing timing of the quantity of generated power, are preset by a parameter setting means 11. If the power consumption increases, the outputs of domestic fuel cells are controlled so that the quantity of generated power determined by subtracting the deviations from the power consumptions, the increase rate of the quantity of generated power, and the increase timing of the quantity of generated power may be obtained respectively, which are outputted from the domestic fuel cells corresponding to the time zone.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling the output of a home fuel cell which outputs generated electric power and supplies it to home electric appliances.

[0002]

2. Description of the Related Art Conventionally, the power output of a home fuel cell has been monitored by monitoring the amount of electric power used in the home, and is controlled so as to follow the value. However, in a fuel cell, the power output is increased after reforming the raw fuel such as city gas to generate a gas mainly composed of hydrogen. I can't follow.

For this reason, for example, when the power output of a fuel cell is made to follow the power of a household electric appliance such as a microwave oven, a toaster, and a hair dryer, which consumes a large amount of power and has a short operation time, the generated output follows the electric power used by the household electric appliance. At that time, the household electric appliance is suddenly turned off, and accordingly, the power generation output of the fuel cell must be reduced. If the increase and decrease of the power generation output are frequently repeated, there is a problem that the life of the fuel cell is shortened.

[0004] In addition, home electric appliances with large power consumption are OF
When F is applied, although the fuel cell has better followability in the output decreasing direction, the generated output may exceed the used power in some cases. When such a situation occurs, in the case of an operation mode in which the power output of the fuel cell is not transmitted to a power system such as a commercial power supply that is interconnected with the grid, that is, a so-called reverse power flow is not performed, the fuel cell may be in an idle operation. In some cases, there was a problem that the fuel cell was shut down unexpectedly.

In order to avoid the above-mentioned problems, conventionally, generally, the power output of a fuel cell is made to follow a smaller value than the power used, and a small amount of power is always received from a power system.

[0006]

However, if a small amount of power is always received from the power system, for example, during nighttime, the power consumption is small, such as standby power or refrigerator power, and the fluctuation is small. Even when power is consumed, there is a disadvantage that the power is received from the power system, the utilization rate of the power generation capacity of the fuel cell is reduced, and the energy saving is reduced.

[0007] The present invention has been made in view of such circumstances, and the invention according to claim 1 focuses on the usage status of home electric appliances and frequently follows the power consumption while generating power. It is an object of the present invention to avoid a sudden change and increase the utilization rate of the power generation capacity, and an object of the invention according to claim 2 is to enable the occurrence of reverse power flow to be suppressed well.

[0008]

According to a first aspect of the present invention, there is provided a method for controlling the output of a domestic fuel cell, comprising the steps of: A fuel cell, a power generation amount output from the home fuel cell and an increase rate of the power generation amount, and output control means for controlling an increase timing of the power generation amount, and a home electric power consumption pattern in a unit period. The unit period is divided into a plurality of time zones in advance, and the deviation subtracted from the used power to obtain the generated power output from the household fuel cell for each time zone, and the rate of increase of the generated power. A parameter setting means for setting an increase timing of the amount of generated power; a use power increase detection means for detecting an increase in the used power and outputting an output control signal; The control means selects and sets the deviation and the increase rate of the generated power amount corresponding to the time zone at the time of output of the output control signal, and the increase timing of the generated power amount from the parameter setting means, and is set. Generated power obtained by subtracting the deviation from the used power, and
The output of the household fuel cell is controlled so that the rate of increase in the amount of generated power and the timing of increase in the amount of generated power are controlled.

According to a second aspect of the present invention, there is provided a method for controlling the output of a domestic fuel cell according to the first aspect of the present invention, wherein the reduction in power consumption is detected by detecting a decrease in power consumption. A power consumption decrease detection means for outputting a signal is provided, and the parameter setting means is set as a decrease rate of the generated power amount for each time period to be larger than the increase rate, and is decreased as a generated power amount decrease timing. Set to start the reduction immediately in response to the output control signal.

[0010]

According to the configuration of the home fuel cell output control method according to the first aspect of the present invention, the power consumption is large based on the domestic power consumption pattern in a unit period such as one day. Divided into multiple time periods, such as a time period during which home appliances are used for a short time and a time period during which they are not used, where power consumption is low and power is continuously consumed with little fluctuation Then, the deviation to be subtracted from the used power to obtain the generated power output from the household fuel cell corresponding to each time zone, and the rate of increase of the generated power, and the timing of increasing the generated power are set in advance. When the amount of power used increases, the amount of power generated by subtracting the set deviation from the power used, which is output from the household fuel cell corresponding to the time zone at that time, and power generation Rate of increase in force, as well as to control the output of the household fuel cell so as to increase the timing of generated power.

Further, according to the configuration of the output control method of the domestic fuel cell according to the second aspect of the present invention, when the amount of power used decreases, the amount of generated power starts to decrease immediately, and Is decreased at a rate of change larger than that at the time of increase, so that the amount of generated power does not exceed the amount of used power.

[0012]

Next, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram for explaining an embodiment of an output control method for a home fuel cell according to the present invention. Various home electric appliances are connected as a load 3 to a power output line 2 from a home fuel cell 1. Have been. A commercial power supply 4 is connected to the power output line 2 as a power system.

A first power meter 5 for measuring the power output from the fuel cell 1 and the commercial power supply 4 on the power output line 2;
A second power meter 6 for measuring the power output from the fuel cell 1 is provided. First and second wattmeters 5, 6
Is connected to the controller 7, and the controller 7
A power regulator 8 (see FIG. 2) for adjusting the output of the fuel cell 1 by controlling the direct current is connected.

As shown in the block diagram of the control system in FIG. 2, the controller 7 includes a power consumption increase detecting means 9, a power consumption decrease detecting means 10, a parameter setting means 11, an output control means 12, a deviation calculating means. 13 and comparison means 14
Is provided. A clock 15 is connected to the controller 7 (output control means 12).

The power consumption increase detecting means 9 detects an increase in the power consumption based on the power consumption measured by the first wattmeter 5 and outputs an output control signal. Further, the power consumption decrease detection means 10 detects a decrease in the power consumption based on the power consumption measured by the first wattmeter 5 and outputs a decrease output control signal.

The parameter setting means 11 preliminarily classifies a plurality of time zones on the basis of a domestic power consumption pattern within one day as a unit period, and generates an amount of generated power output from the fuel cell 1 for each time zone. An increase rate and a decrease rate of the generated power amount, and an increase timing of the generated power amount are set.

The amount of power generated from the fuel cell 1 is as follows.
This is the power generation output obtained by subtracting a predetermined deviation (offset) from the used power. The rate of increase and decrease in the amount of generated power means the rate of change when the output increases and the rate of change when the output decreases. The increase timing of the generated power amount means a dead time (waiting time) from receiving each of the output control signal and the decrease output control signal to outputting a drive signal for performing control.

That is, for example, as a household electric power consumption pattern within one day, a pattern shown in a graph of a temporal change of instantaneous electric power in a dwelling unit in FIG. 3 is obtained. Based on this consumption pattern, it is divided into the following three time zones. Here, it is assumed that the fuel cell 1 has a maximum generated power of 500 W.

"From midnight (0:30) to early morning (7:00
0 minutes) "The change in the amount of power used during this time period is standby power or power of a refrigerator, etc.
The amount of power is also small. Therefore, the parameters are set as follows. When output increases When output decreases Rate of change: 5% / min Instantaneous dead time: 0 minutes 0 minutes Offset: 5% (25W) 5% (25W)

"Daytime (7:00 to 17:30)" The change in the amount of power used during this time period depends on the ON / OF of home electric appliances such as electric rice cookers and microwave ovens which consume a large amount of power.
F, furthermore, fluctuations considered to be about 100 W of lighting, vacuum cleaner, etc. are seen. The parameters are set as follows in view of the fact that the operating range of the power consumption is large and the operation is performed for a relatively long time, and that there is a small capacity fluctuation. When the output increases When the output decreases Change rate: 10% / min Instantaneous dead time: 1 minute 0 minutes Offset: 10% (50W) 10% (50W)

[Night (from 17:30 to 0:30)
Minutes)] The amount of power consumed by lighting has increased, and devices with large power consumption, such as washing machines and dryers, have also been turned on / off. The changes in baseload are similar to those in daytime,
Because fluctuations in the amount of power consumption occur relatively quickly,
It is important to avoid a sudden change in the power generation output by increasing the dead time, and the parameters are set as follows. When output increases When output decreases Rate of change: 10% / min Instantaneous dead time: 2 minutes 0 minutes Offset: 10% (50W) 10% (50W)

The output control means 12 receives the time from the clock 15 and responds to each of the output control signal and the reduced output control signal in response to power generation output from the fuel cell 1 corresponding to the time zone when the signal is output. The deviation to be subtracted from the power used to obtain the power, the increase rate of the generated power, and the increase timing of the generated power are selected and set from the parameter setting means 11, and the set deviation is subtracted from the used power. A drive signal is output to the power regulator 8 so that the generated power amount, the generated power amount increase rate, and the generated power amount increase timing are controlled, and the output of the fuel cell 1 is controlled. .

The deviation calculating means 13 inputs the power consumption and the power generation measured by the first and second wattmeters 5 and 6, and calculates the deviation (offset) between the power consumption and the power generation. It is supposed to. The first wattmeter 5 may be provided at a location where the power output line 2 and the commercial power supply 4 are connected to measure the amount of power (commercial power) received from the power system. It has the advantage of measuring itself.

The comparing means 14 compares the deviation calculated by the deviation calculating means 13 with the deviation selected and set by the parameter setting means 11 and obtains the amount of generated power in which the two deviations are equal to each other. And a drive signal is output to the power regulator 8 by the output control means 12 so that the amount of generated power is obtained, thereby controlling the output of the fuel cell 1.

According to the above configuration, when the increase in the amount of power consumption is detected, the dead time, the rate of change, and the deviation (offset) corresponding to the time zone when the output control signal is output are selected and set. As shown in a time chart for explaining the control operation of FIG. 4A, a deviation (offset) is set for the used power at a change rate set after a set dead time. The output of the fuel cell 1 can be controlled so as to increase the amount of generated power up to the output of generated power (power generation output). Therefore, when the home electric appliance is turned off during the dead time, the amount of power generated by the fuel cell 1 is not increased, and a sudden change in the power output of the fuel cell 1 can be avoided.

On the other hand, in response to the detection of the decrease in the power consumption, in response to the decrease output control signal, as shown in a time chart for explaining the control operation of FIG.
It is possible to instantly reduce the amount of generated power without having a dead time, thereby avoiding the generation of reverse power flow due to the amount of generated power being larger than the amount of used power.

In the above embodiment, the unit period is set to one day, but may be set to a predetermined unit period such as one week. Further, the unit period is divided into three time zones, but may be divided into two or four or more time zones.

[0028]

As is clear from the above description, according to the method for controlling the output of a domestic fuel cell according to the first aspect of the present invention, the power consumption pattern of the household power within a unit period such as one day can be reduced. Based on the time period, the unit period is divided into a plurality of time zones in advance, and when the amount of power consumption increases, the output is output from the home fuel cell obtained by subtracting a preset deviation from the power consumption in accordance with the time zone at that time. Power generation,
Also, since the output of the household fuel cell is controlled so that the rate of increase in the amount of generated power, and the timing of increase in the amount of generated power, for example, a time period during which home electric appliances with a large power consumption and a short operation time are not used Then, compared to the time period when these home appliances are used, the amount of generated power output from the home fuel cell is adjusted to a value close to the amount of used power and the rate of increase is made smaller so as to follow the received power from the power system. It is possible to increase the utilization rate of the power generation capacity by minimizing the amount of electric power and improve energy saving. On the other hand, in a time zone in which home electric appliances having large power consumption and a short operating time are used, the timing of increasing the amount of generated electric power is delayed, so that the power generation output by following the short-time ON / OFF of the home electric appliances is reduced. Frequent sudden changes can be avoided, the performance of the fuel cell can be changed stably, and the life can be extended.

According to the configuration of the home fuel cell output control method according to the second aspect of the present invention, when the amount of power used decreases, the amount of power generated by the fuel cell is made instantaneous, and the amount of generated power is used. Since the amount of electric power is not increased, the generation of reverse power flow can be suppressed well, and the performance of the fuel cell can be changed more stably to extend the life.

[Brief description of the drawings]

FIG. 1 is a block diagram for explaining an embodiment of a home fuel cell output control method according to the present invention.

FIG. 2 is a block diagram of a control system.

FIG. 3 is a graph showing a temporal change of instantaneous electric power in a dwelling unit.

FIGS. 4A and 4B are time charts for explaining a control operation, in which FIG. 4A shows a case where power consumption increases and FIG. 4B shows a case where power consumption decreases.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Fuel cell 9 ... Power consumption increase detection means 10 ... Power consumption decrease detection means 11 ... Parameter setting means 12 ... Output control means

Claims (2)

[Claims] 1. A home fuel cell that outputs generated power and supplies it to home electric appliances, a generated power amount output from the home fuel cell, an increase rate of the generated power amount, and an increase timing of the generated power amount. Output control means for controlling, and the unit time period is divided into a plurality of time zones in advance based on the consumption pattern of home electric power in the unit time period, and the generated power amount output from the home fuel cell for each time zone. Parameter setting means for setting a deviation to be subtracted from the used power and an increase rate of the generated power amount, and an increase timing of the generated power amount, and detects an increase in the used power amount and outputs an output control signal. Power consumption increase detection means, and the output control means, wherein the deviation corresponding to a time zone at the time of output of the output control signal and the rate of increase in the amount of generated power, In addition, an increase timing of the generated power amount is selected and set from the parameter setting means, and the generated deviation is obtained by subtracting the set deviation from the used power, and an increase rate of the generated power amount, and an increase of the generated power amount. An output control method for a home fuel cell, comprising controlling an output of the home fuel cell so as to be in timing. 2. The output control method for a household fuel cell according to claim 1, further comprising: a power consumption decrease detection unit that detects a decrease in the power consumption and outputs a decrease output control signal, and wherein the parameter setting unit includes: In addition, the rate of decrease in the amount of generated power for each time period is set to be greater than the rate of increase, and the timing for decreasing the amount of generated power is set to immediately start decreasing in response to the decrease output control signal. An output control method for a home fuel cell.